Robin Van Persie, £24 Million

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Many people questioned Ferguson’s decision to bring Robin Van Persie to Old Trafford in the summer of 2012.

The Dutchman had just turned 29, only had one year left on his contract, and despite having shown his striking pedigree at Arsenal over the previous 18 months, his consistent injury problems had blighted his Gunners’ career.

Ferguson knew though that his goals would prove to be the difference between United and Manchester City, who had pipped his side to the title on goal difference just months earlier.

Between August and March, Van Persie’s attacking demeanour helped lead United to a gargantuan Premier League advantage over their closest rivals, and despite the fact that his form has recently cooled, Van Persie’s first season for the club has still been a resounding success.

Wayne Rooney, £27 Million

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Manchester United paid the highest ever transfer fee for a player under 20 when they acquired the services of Wayne Rooney from Everton in 2004.

And during his time at the club Rooney has not only claimed 4 Premier League titles and 1 UEFA Champions League trophy, but he has also produced numerous moments of quality that will forever live in the memories of United fans across the world.

But having been dropped for United’s crucial second-leg encounter against Real Madrid last month, rumours now continue to circulate that he could be on his way out of Old Trafford.

Even if he does leave the club over the next few months, his time at United will still be deemed a success.

Rio Ferdinand, £29.3 Million

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During his eleven years at Old Trafford Rio Ferdinand has blossomed into one of the greatest defenders in England.

Ferdinand’s strength, skill and pace has been at the heart of Ferguson’s defence for the last decade and his formidable partnership with Nemanja Vidic is regarded as one of the sternest in Premier League history.

The astronomical sum of money that United spent on Ferdinand back in 2002 now looks to have been a steal.